Identifying and Treating Pneumonia in Newborn Calves

Calf pneumonia is also known as BRD (bovine respiratory disease) or shipping fever. It most commonly occurs in stressed animals and is the second most common cause of death in calves. Pneumonia in calves is primarily problematic in calves under 6 months of age with peak incidences from 2 to 10 weeks of age. However, it is not uncommon in calves up to 1 year of age. There are many products to help prevent and treat calf pneumonia in calves. Prevention is much less expensive and less labor intensive than treatment after illness has set in. Prevention tactics are discussed later in this article.

Environmental Factors and Calf Pneumonia

BRD can develop due to one or a combination of the following factors:

• Environmental stressors
• Poor calf husbandry
• Disease pathogens
• Insufficient passive immunity transfer from the dam to the calf

Symptoms are sometimes noted after a period of stress or life event, such as dehorning, castrating, weaning, commingling, and transporting. Mixing and crowding of calves during such management tasks enhances the transmission of infectious agents among animals. Stress inherently weakens the immune system, allowing viruses or bacteria to develop in the lungs and cause illness. Pneumonia can cause permanent lung damage, making it a challenge for the calf to thrive. Through improved environmental and management procedures, preventing pneumonia is best for healthier, better performing calves.

What Are the Causes of Calf Pneumonia?

The development of this disease begins when the animal is involved in an environmental or managerial stressor, and possibly an initial respiratory infection followed by secondary bacterial infection of the lower respiratory tract. While environmental factors can enhance the risk of pneumonia in calves, bacteria, viruses, or a combination of both are the causes of calf pneumonia.

Viral Pneumonia in Calves

Viral pneumonia in calves is caused by BRSV, PI3, IBR, BVD type 1 and 2 viruses which affect the upper portion of the lungs. Although these viruses are not usually fatal by themselves, they do cause lung damage and suppress the immune system allowing secondary bacterial infections to settle in.

Let’s take a closer look at the viruses that cause calf pneumonia:

• BRSV (bovine respiratory syncytial virus)
  • Primary bovine respiratory pathogen.
  • Mostly occurs in young beef and dairy cattle.
  • Can cause acute and severe pneumonia with multiple reinfections resulting in milder symptoms.
• PI3 (parainfluenza type 3)
  • Causes mild to subclinical respiratory infections.
  • Precursor to secondary bacterial pneumonia.
• IBR (infectious bovine rhinotracheitis)
  • A herpes virus which causes changes in the cell so the lymphocytes do not recognize it as a foreign body and do not attack it.
  • Highly contagious, airborne, and spread by direct contact.
  • Can be latent until the animal is stressed.
• BVD (bovine viral diarrhea type 1 and 2)
  • Suppresses the immune system, increasing the calf’s susceptibility to other infections.
  • Spread through breeding—a calf infected with BVD before birth is considered persistently infected (PI) and will shed the virus.
    • Test for PI calves and remove them from the pen to mitigate disease transmission.

Bacterial Pneumonia in Calves

Bacterial pneumonia strains are naturally present in the nasal passages and when the animal’s immune system is compromised it migrates to the lower respiratory tract, causing infection in the lungs.

Bacterial pathogens include:

• Mannheimia haemolytica (shipping fever pneumonia)
  • Primary cause of bacterial pneumonia.
  • Causes severe, acute, fatal pneumonia—if the calf survives, there may be permanent lung lesions.
  • Often associated in a feedlot setting where large groups of calves from different geographic, nutritional, and genetic backgrounds assemble.
• Pasteurella multocida
  • Secondary bacterial infection influenced by primary stress or viral infection.
  • Causes less severe pneumonia in comparison to M. haemolytica with limited lung lesions and puss pockets in the lungs.
  • Common cause of pneumonia in dairy calves.
• Histophilus somni (Haemophilus somnus)
  • Causes infection and inflammation in the lungs.
  • Can spread from the lung to other locations in the body such as brain, heart and joints, causing infection in these areas.
• Mycoplasma bovis
  • Causes respiratory disease, arthritis, and ear infection (head tilt) in feedlot cattle, and young dairy and veal calves.
  • In chronic conditions, the disease does not respond to antimicrobial therapy.

What Are the Symptoms of Calf Pneumonia?

Physical symptoms of pneumonia in calves are fairly easy to see and understand:

• Nasal discharge—a runny nose, varying from unilateral-to-bilateral discharge and mild-to-copious amounts of discharge.
• Cough—coughing, ranging from an induced single cough in mild cases to repeated spontaneous cough in more severe cases.
• Respiratory issues—difficulty breathing and/or open-mouthed breathing.
• High fever—a rectal temperature ranging from 101 or 101.9 °F to 103 °F or higher.
• Eye discharge—minor to heavy amount of ocular discharge depending on the severity of disease condition.
• Ear and head position changes—slight flick or head shake in calves with mild symptoms, head tilt and bilateral droopy ears in calves with more severe symptoms.

How is Calf Pneumonia Diagnosed?

If you suspect pneumonia in your calf herd, contact your veterinarian for further testing and diagnosis:

• Your veterinarian can perform a necropsy on deceased calves and send tissue samples of the lungs to a diagnostic lab to test for causative pathogens.
• For suspects of persistently infected BVD calves, an ear notch or blood sample can be collected and tested.
• Nasal, tracheal, and nasopharyngeal swabbing can be performed by your veterinarian.
• More in-house tests are becoming available requiring a serum or plasma and can be performed by your veterinarian.

What Are the Best Calf Pneumonia Treatments?

Treatment of pneumonia in calves is very important once you are see the signs and you’ll want to take immediate action.

Antibiotics

Immediately treating calves with a respiratory antibiotic at first signs of symptoms can help reduce the severity of infection. Treatment should continue for 48 hours after symptoms have subsided. However, once pneumonia has settled in and caused significant lung damage, antibiotics will not be effective.

Anti-Inflammatory Medicines

Calves also benefit with the use of anti-inflammatory medications alongside antibiotics as they reduce inflammation in the lungs and reduce fever. The following antibiotics are beneficial as they include anti-inflammatory medication in one convenient dose:

Prophylactic treatment

The term Metaphylaxis refers to administering antibiotics at first sign of onset, or prior to symptoms, in animals at high risk of developing pneumonia. When a new shipment of cattle have arrived on the farm and at risk of developing shipping fever pneumonia, this is an ideal time for prophylactic treatment.

Antibiotic products labeled to treat BRD in calves include:

The practice of Metaphylaxis is shown to significantly reduce mortality and improve rate of gain while preventing the calves from contracting disease or furthering their illness.

How to Prevent Pneumonia in Calves

Prevention is key to keeping your newborn and young calves from contracting pneumonia. It helps keep them healthy and productive, reduces mortality rates, and saves producers from the hassle and great expense in treating an already developed pneumonia issue.

Management Practices to Curb Pneumonia in Calves

Watch these factors to help reduce the risk of pneumonia and other illnesses in your newborn calves.

• Nutrition—newborn calves should receive adequate amount of good quality colostrum to help fend off disease.
  • Feed high quality milk replacer or whole milk until 8 to 12 weeks of age.
• Calf Housing—place newborn calves in individual hutches.
• Environment—bedding and pens should be clean and dry to minimize lung damage from ammonia.
• Ventilation—always provide fresh, draft-free air to calves.
  • Individual calf-hutch housing provides good natural ventilation.
  • Group housing can benefit from positive pressure ventilation systems.
• Grouping—calves should be of similar age when assembled into groups and limited to 10 or less to prevent overcrowding.
• Stress Minimization—avoid multiple stressors at once such as weaning, castration, dehorning, and transportation.
  • Space these management procedures in time-frame which is practical yet minimizes stress.
  • Handle with care—use low-stress handling techniques.
  • Apply FerAppease—use before and during stressful events to reduce the effects of stress.
    
    

Vaccines for Calf Pneumonia Prevention

You have multiple opportunities to provide vaccination protection for your calves, even before they’re born!

• Vaccinate the cows against respiratory viruses and bacteria 3 to 4 weeks prior to calving to improve the quality of colostral antibodies.
• Vaccinate calves 3 to 4 weeks before first grouping or weaning.
• Intranasal vaccinations can be given to calves as young as 3 days of age or older, including pregnant cows, to prevent viral and bacterial pneumonia infections.

With proper management practices in calf husbandry, reducing stress and vaccination protocols can help mitigate the negative impact pneumonia can have on your calves.

Always consult your veterinarian if you have question or concerns regarding prevention, treatment, or diagnosing pneumonia in your calves.

Find all calf pneumonia vaccine prevention here!

Find all calf pneumonia antibiotic treatments here!